Department of Tissue Engineering

Head: Mgr. Eva Filová, Ph.D.

The research of the Department is focused on the development of artificial tissues, mainly biodegradable scaffolds for tissue regeneration, such as nanofibers, foams, and hydrogels for the regeneration of cartilage, bone and incisional hernia. We also focus on computer modeling of protein structures. We are developing the technology of controlled drug delivery from nanofibers scaffolds with liposomes for targeted release of drugs into the defect. The work is also concentrated on the development of three-dimensional nanofibers, using novel technique of Forcespinning®. These nanofibres are more suitable for cell growth and differentiation. Moreover, high on our priority list is also the accelerated transfer of newly developed technologies and know-how into clinical practice. We are developing artificial scaffolds for the regeneration of bone and cartilage in clinical practice.

2. We have developed polypropylene (PP) surgical mesh coated with PCL nanofibers with adhered thrombocytes as natural source of growth factors.

The composite mesh with thrombocytes showed improved fibroblasts adhesion, proliferation, and metabolic activity compared to PP, PP coated with nanofibers, and PP functionalized with thrombocytes. The system of composite scaffold with growth factors released from thrombocytes is promising approache for tissue engineering.

Important results in 2015

1. Functionalized nanofibers for controlled drug deliveryThe system of functionalized nanofibers with controlled drug delivery has been developed and optimized. This system has been applied for treatment of incisional hernia. Polypropylene surgical mesh was modified by PCL nanofibers covering and functionalised with adhesion of growth factors. Samples were tested in vivo on a rabbit model as a model for prevention of incisional hernia formation.

2. Biomechanical testing of the repaired abdominal wallAbdominal closure was reinforced by application of polypropylene mesh functionalized with poly-ε-caprolactone nanofibers and growth factors. This novel arrangement is going to be used for prevention of incisional hernia formation. However, the system seems to be very general and there is intended for much broader chirurgical and orthopedical application.

Histological evaluation. Collagen, adipose tissue, and granulomatous infiltration in the scaffolds under study. In samples without any mesh (A), the incision was healing with a mixture of collagen (black arrow), adipose connective tissue (red arrow) and inflammatory infiltrate (yellow arrow). Samples with polypropylene (PP) mesh (B) had a high fraction of adipose tissue, but the spaces showing the dissolved mesh (black arrows) were surrounded by only a few inflammatory cells. Remnants of the nanofibers (C, D, E, F) were surrounded by granulomatous leukocyte-rich connective tissue (yellow arrows in C, D, E, F). The highest fraction of collagen (red arrow) was in samples of PCL nanofibers with adhered growth factors (GF) (D), followed by samples with no mesh (A) and by samples of PCL nanofibers (F). Low fractions of adipose tissue were found in samples of PCL nanofibers with adhered GF (D), samples with no mesh (A) and in samples of PCL nanofibers (F).

Important results in 2013

1.Time-regulated drug delivery system based on coaxially incorporated platelet alpha granules for biomedical useAlpha granules are novel source of natural growth factors from platelets. In recent work we had sucesfully embedded alpha granules into nanofibers with core/shell structure. The alpha granules survived the electrospinning proces and growth factors retained their bioaktivity as was demonstarted on the model of chondrocytes and mesenchymal stem cells.

2. A cell-free nanofiber composite scaffold regenerated osteochondral defects in miniature pigsA novel drug delivery system was developed on the basis of the intake effect of liposomes encapsulated in PVA nanofibers. Time-controlled release of insulin and bFGF improved MSC viability in vitro. In addition, cell-free composite scaffolds containing PVA nanofibers enriched with liposomes, bFGF, and insulin were implanted into seven osteochondral defects of miniature pigs; control defects were left untreated. The cell-free composite scaffold enhanced migration of the cells into the defect, and their differentiation into chondrocytes; the scaffold was able to enhance the regeneration of osteochondral defects in minipigs.

3. Electrospun core/shell nanofibers: a promising system for cartilage and tissue engineeringAlpha granules are novel source of natural growth factors from platelets. In recent work we had sucesfully embedded alpha granules into nanofibers with core/shell structure. The alpha granules survived the electrospinning proces and growth factors retained their bioaktivity as was demonstarted on the model of chondrocytes and mesenchymal stem cells.